MDCT venography in patients with suspected pulmonary embolism: diagnostic impact of pelvic vein evaluation in thromboembolic disease detection

AIM: To assess the incremental value of pelvic vein-evaluation with Multidetector CT Venography (MDCT-V) for the diagnosis of thromboembolic disease in patients suspected of Pulmonary Embolism (PE). METHODS: We retrospectively reviewed CT images of 440 patients (228 women and 212 men; mean age 63 ± 18 years) who underwent combined Multidetector CT Pulmonary Angiography (MDCT-PA) and MDCT-V for suspected PE. Frequency of PE, deep venous thrombosis (DVT), and venous thromboembolism (VTE) were assessed together with the incremental value of MDCT-V; the distribution of thrombi and the frequency of isolated clots in the inferior vena cava or iliac veins were also recorded for each patient. RESULTS: PE was detected in 146 (33%) of 440 patients, DVT in 147 (33.4%) and VTE in 196 (44%). MDCT-V showed thrombi in 50 patients who did not have signs of PE at MDCT-PA. Thus, the addition of MDCT-V resulted in a 25% increase in thromboembolic disease detection (99% confidence interval: 22%, 28%). Among 147 patients with DVT, only four had thrombi in the iliac and/or in the inferior vena cava without femoral or popliteal vein thrombosis; however, all but one had also PE detected on MDCT-PA. Thus, the diagnostic value of MDCT pelvic vein evaluation was 2.7% in the diagnosis of DVT and 0.5% in the diagnosis of VTE. CONCLUSION: In patients with suspected PE, evaluation of pelvic veins with MDCT-V has a limited impact on the diagnosis of thromboembolic disease and could be safely omitted